Musical instrument



June 5, 1928. 1,672,153

J. DOPYERA MUSICAL INSTRUMENT Filed Aug. 16, 1924 2 Sheets-Sheet 1 June5, 1928.

J. DOP'YERA MUS ICAL INSTRUMENT Filed Aug. 16, 1924 2 Sheets-Sheet 2nix.

Patented June 5, 1928.

1,672,153 PATENT OFFICIE.

UNITED STATES;

JOHN DOPYERA, O1- LOS ANGELES, CALIFORNIA.

MUSICAL INSTRUMENT.

Application filed August 16, 1924. Serial No. 732,465.

This invention relates generally to musical instruments and moreparticularly to string instruments such as banjos, mandolins, guitarsand the like, and has fora main object the provision of an instrumentwith an all metal body composed of a plurality of thin metallic membersdetachably held together, and so arranged as. to provide a highlyresonant instrument and embodying details of improvements not heretoforeused in instruments of this type. 7

Another object is to provide an instrument having a body composed of ahollow metallic band over which a skin is adapted to bestretched as inthe case of a banjp, or to which the sounding board may be suitablyattached as in the case of a mandolin and: guitar, and provided on theback thereof with a substantially enlargedhollow cover forming a primaryresonator by means of which the-vibrations set up when the instrument isplayed will be amplified and louder and moresustained tones providedthan is possible in obtaining types of such instru ments.

Another object is to provide an auxiliary resonator enclosed'by saidcover and supported thereon for still further amplifying the soundproduced when the instrument is played. v

Another object is to provide means whereby theseveral part-s of'theinstrument may be detachably held together so that the same maybequickly assembled and dis-assembled. as hereinafter more particularlydescribed.

I have shown one practical embodiment of my invention in theaccompanying draw-- ings, applied to a banjo, in which similarcharacters of reference are employed throughout the several views forindicating the same and like parts.

In said drawings: Fig. 1 is a top planview of the instrument withtheneck partially broken away.

Fig. 2 is a side elevation of the same, partly in section.

Fig. 3 is a bottom plan View of the with the resonator cover removed.

F ig. 4. is a typical transverse section of same,

the same on line of Fig. 1.

Fig. 5 is a transverse section of. the sameon line 5-5 showing amodified form and arrangement of the cover...

Fig. 6 is a diametrical section of the cover r and resonator of slightlymodified form from. thatshown in Fig. 2.

be observed that the same embodies as primary parts thereof an annularband or ring B to the top of which the usual skin S. is applied and heldin position. by means of a narrower band I); a cover-C on the back ofthe instrument is adapted to be removably held on the band. B and aresonator R which is enclosed by the cover C and is supported thereon asshown in Fig. 2. The arrangement and connections of the membersdescribed. are more clearly shown in Fig. 4, which I will now describe.

The band B isof thin sheetv or cast metal and partakes' of the form of acontinuous ring of lighter weight metal, such as aluminum. An, outerband B encompasses the.

band B and has its upper edge portion 6 turned outwardly: forasubstantial distance v around the. central portion thereof, and

I thence inwardly where it abuts the outer periphery of band B, thusproviding a flange as at f of double thickness wherewith to provide asupport for the cover C.

Theskin S ,is tightly stretched over the curved portion. e of the outerband B as shown in Fig. 4, and. extends downwardly over the outerperiphery of sa-id band B and thence outwardly, upwardly and inwardlyover the four sidesof a rectangular ring T which encompasses the bodyportion of band B. The skin retaining band 6 is also curved at itsupperedge and has an annular groove g formed therein which is open on theouter periphery of the band and is so formed that an upwardly extendedannular rib 1 is provided at. the bottom of the open part of saidgroove, whereby a plurality of rods2, mayv beattached to. the band 6 bymeans of hooks h'fo-rmed on the upper ends of said members and adaptedto fit in the groove 9 and to overlie the annular rib 1.

The lower ends of the members 2 are threaded at 3 and extended throughopenings 4 in the flange f of the outer band B and are provided belowsaid flange with nuts 5, which are threaded onto the lower ends of saidmembers 2, so that when said nuts are tightened the members 2, will bedrawn downwardly and the band 6 will be also drawn downwardly over theouter portion of band B, the band 6 having an annular recess at 6 formed011 the inner side thereof and at the bottom'for receiving the edgeportion of theskin S and the ring r. Thus, when the'band b is drawndownwardly by tightening the nuts 5, the ring 7 will also be drawndownwardly and the skin S will be tightened over the upper edge e ofband B.' i

, The cover C is integrally formed of sheet or cast metal and rolled ormolded into the form shown, and it will be noted that the diameter ofthe said cover is substantially larger than the diameter of the head ofthe instrument.

The cover C has an annular outer portion 7 .of semi-circular crosssection with an in wardlyturned flange 8 underlying the flange f ofbands B, and said cover is detachably held on said band B by means of aplurality of screws 9, with the heads thereof underlying the flange 8 ofthe cover, and the outer ends thereof extended through said flange 8 andthe two thicknesses of metal composing the'flange f of member B and nuts10, are provided on the upper side of said flange f, which are threadedonto the ends of the said screws for holding the cover firmly inposition and in concentric relation with the body band 6. p

The cover is provided on its upperiside and externally of the flange 7with a plurality of openings 0, whereby the tones produced by theplaying of the instrument may be emitted in substantial volume. Theouter portion 7 of said cover continues inwardly forming a back portiona which is flared outwardly for a substantial distance as-shown in Fig.2, and said portion a is substantially spaced from the portions 6 of theband B, so that the cover is held in contact with the band B" only atpoints near the" outer periphery of the flange f, so that the vibrationsset up by the playing of the instrument may be amplified to a'maximumextent and the tones will not be impaired by contact with other parts ofthe instrument;

The resonator R is also formed of thin metal and may be adjustablyhel'd'on the cover C, as shown in Fig; 2, or fixed thereto at the edge,as shown in Fig. 6, as occasion may warrant. In some cases and on someinstruments, depending upon the size and cave portion 11, and theresonator R is similarly provided with a concave portion 12 in thecenter thereof so as to provide means for adjustably connecting theresonator R with the portion a, of cover C. This connection isaccomplished by means of a stud 13 which is threaded into the portion12'of the resonator which is reinforced by means of the washer 14-soldered or otherwise at-.

tached thereto for providing additional threads, and the outer end ofsaid stud is extended through the portion 11 of the cover and isreversely threaded into a detachable head 15 carried on the outer end ofsaid stud, whereby the stud may be turned for moving the resonatorrelative to the back of the cover C. A spring 16 is carried on the stud13 between the portion 11 of cover 0 and the portion '12 of resonator Rwhich exerts tension on the resonator for preventing the turning thereofwhen the stud is turned.

The outer edge 17 of the resonator is annularly formed and is adapted torest against the flat portion a on the back of cover C, or as occasionmay arise, when the stud13'is turned the edge 17 may be adjusted-so asto be spaced from the portion a of the cover. The vibrations produced inthe playing of the instrument are modified toa greater or less extent byreason of the be desirable in some cases to dispense with the adjustableconnection between the cover C and resonator R, and in such. case, asshown in Fig. 6, the portions 11 and 12 of the cover and resonatorrespectively, are

omitted and the annular portion 17 of the resonator may be soldered orotherwise attached permanently to the portion a of the cover C at points18, as shown.

The neck N of the instrument is attached to the bands B and B so as tobe capable of x I removal therefrom as shown in Fig. 3. For this purposea metallic rod 20 is extended diametrically across the interior of theinstrument at a point about midway of the portions 6 and e, and one endthereof is attached to said hands by means of a screw 21 having its headon the outer side of band B, and having its threaded stem screwed intothe end 22 of said rod, one or more washers 23 being providedbetween'the end of the rod and the band B as shown in Fig. '3. i

The other end of rod 20 is adapted to be attached to the neck N by meansof a screw 24 which has a square or hexagonal head 25 adapted to seat inand tobe non-rotatively held in a correspondingly formed recess 20 screw21 in the othcrend of said rod may be I flange f of band B threaded intosaid end of the rod and the neck N will be drawn tightly against theouter periphery of band B and will be lirmly and substantially held inposition for holding the instrument during use.

The tail piece T is applied to the Outer side of the band B as in thecase of other instruments and at a point on the diametric,

line of the neck N so that the upper portion of said tail piece willoverlie the skin S and strings W, WV, VW and are suitably attached tosaid tail piece and are held in spaced relation with respect to'the skinS, by means of the usual bridge (5. The strings are adapted to bestretched to the proper tension by means of the usual keys (not shown)mounted on the outer end of the neck N.

Referring to Fig. 5, I may find it convenient and desirable to form thecover C of two pieces of thin metal instead in Fig. 4, so that the samemay be more readily rolled into desired form. In this case the upperpart of the cover will be provided with the portion a underlying the asin the other form, but the outer portion of said band is preferablyturned upwardly around the outer edge of flange f to a point flush withsaid upper edge, and thence rolled outwardly and downwardly where thelower edge thereof may be connected with the lower part of the cover bymeans of an interlocking head 30, and the lower part continues thencedownwardly and inwardly where it will join the portions a and a forforming. the continuous closed cover shown in the other form of device.

It is desirable in many cases in the provision of an instrument of thiskind to provide means for lighting the interior of the instrument,especially during performances, and to this end the internal rod 20which reinforces the interior of the instrument and also serves tosupport the neck N affords opportunity for conveniently mounting a pairor more of electric lights, as at L and L within the instrument. Saidlights are attached to sockets 31, and 31" respectively, which arecarried on bars 32 and 82 attached at their innner ends to arms 33 and33 formed on a central sleeve 34 which is clamped on the rod 20 by meansof a screw 35. Members d and 32 are attached reof one, as shownspectively to the arms 33 and 33 by means of screws 36 and 36 and thesleeve 34 is insulated from the rod 20 by means of a bushing 37 ofinsulating material.

The bands B and B are provided with openings 38 therein at a point nearthe tail piece T by means of which connection may be made between thelamps .L and L with a source of electric current supply. This connectionincludes a socket 39 which is carried in a clamp device 40 formed ofsheet metal and having a socket receiving portion 41 adapted to beclamped tightly around the socket at the ends 42 thereof by means ofascrew 43 and a lower portion 44 adapted to be attached by suitable meansto the band B on the interior of the instrument. A plug 45 is connectedin the usual maimer to the socket 39 and has wires 46 and 47 adapted toconnect with the source of electric current. The socket 39 has two pairsof wires 48 and 49 and 48 and 49 which lead to the lamps L and Lrespectively,'so that the lamps will be energized for illuminating theinterior of the instrument when the plug 45 is attached to the socket39.

Now it will be understood that in the provision of the instrument hereinshown and described, I have provided numerous improvements overobtaining and heretofore known types of-instruments, said improvementembodying an instrument having an all metal body formed of thin sheetmetal of light weight and subtituting, for instance, the light metallicband B for the usual wooden band which is employed in instrumentsheretofore known and used. Also, by means of the structure shown anddescribed, the lugs as employed for attaching the members 2, to theinstrument have been eliminated and altogether a more ornamental andsightly instrument is provided than is possible with the well knowntypes of such instruments. V

The metal bands, in addition to being of light weight are susceptible togreater orna mentation than their equivalent in wooden bands, as thesame may be plated in gold or silver throughout and otherwise ornamentedas may be desired. Furthermore the connections between the. severalparts of the instrument are such that a novice may readily assemble anddisassemble the instrument, and greater tone values are possible with aninstrument of this kind than with instruments employing wooden bands ofthe character heretofore known and used.

It will be understood that I may modify edge portions bent inwardly overthe edges of said ring and an outwardly extending annular'flangeintermediate said edge portions, a metallic cover over the backof said instrument having a-peripheral portion of a'rrcuate crosssection of substantially greater diameter than said band and having theedge thereof bent inwardly under the flange of said band, and means fordetachably supporting said cover on said band.

2. 'A stringed musical instrument as characterized in claim 1, includinga metallic resonator supported onand inwardly of said cover and spacedfrom said ring and said band.

3; A stringed musical instrumentas characterized in claim l,'1'nclud1nga resonator spaced from said ring and said band, 'and ly formedcuppedportion, an adjusting'screw connecting said cupped port-ions, and aspring on said screw compressed between said cover and said resonatorfor holding said members in adjusted positions.

J OHN DQPYERA.

